Many devices commonly include various positioning systems to determine a current or past location of the device. For example, a smartphone, vehicle, or other device can be equipped with a global positioning system (GPS), a positioning system that determines location relative to WiFi broadcast beacons, or other positioning systems to assist in determining a current location of the device at a particular time. Knowledge of the location of the device can assist in many endeavors, including navigation, data collection, self-driving vehicles, or any other task in which knowledge of the location of the device is beneficial.
However, typical positioning systems and sensors generally suffer from some degree of noise, malfunction, or other inherent limitations. As an example, GPS can fail to provide location determination when the device is located within a building. For example, the signals from the GPS satellites may fail to penetrate the building and be sufficiently received by the device, rendering the GPS positioning system unable to determine a precise location.
As buildings can typically have one or more WiFi transmitters, WiFi navigation can represent one potential solution to the failure of GPS to properly operate in an indoor environment. However, WiFi navigation typically depends on signal strength measurements and WiFi signals are reflected by metallic objects and absorbed by walls, people, and other objects. Therefore, since the WiFi signal strengths are not accurately predictable in practice, WiFi navigation generally is not capable of providing a precise measurement, particularly in the context of a crowded indoor environment.
As another example, existing car navigation systems may struggle to properly operate in severe weather. For example, optical sensors included in a self-driving car system may suffer from decreased efficacy when rain, snow, road salt, or other contaminants obscure the sensor. In addition, if the system relies upon matching of observed terrain to a pre-existing map, then the presence of deep snow drifts or other environmental changes will reduce the system functionality.